The Norwegian came in for heavy criticism following the Hoops' exit to Maribor in the Champions League play-off in midweek.

Indeed, there have been questions over the former Stromsgodset manager's signings, tactics and team selections since the start of the season, all of which came to a head following the 1-0 defeat by the Slovenians which put them through 2-1 on aggregate and which left the Scottish champions in the Europa League.

However, Lawwell told the club's official website: "We can't panic, we've got to keep the head for the longer term

"You need time in a period of transition and you've got to make allowances for a new manager. Nothing prepares you for the Celtic job.

"We have the Europa League and we need to do the best we can and we have a (domestic) treble to go for.

"We have to do the best thing for the club and its supporters for the longer term.

"He has new ideas, new philosophies and he still has the transfer window in terms of brining in players.

"There has been an awful lot to deal with.

"We have every confidence in him and we will back him like we backed all our other managers here, financially and with every support he can get and I am sure he will build a team we will all be proud of."

Lawwell has also come in for stinging criticism for a perceived lack of investment in the club's playing squad.

Having featured in the Champions League group stage in the past two seasons, Celtic will now play Salzburg, Dinamo Zagreb and Romanian side Astra in the much-maligned Europa League.

The Scottish champions have brought in Jason Denayer, Jo Inge Berget, Aleksandar Tonev and Wakaso Mubarak on loan deals as well as goalkeeper Craig Gordon on a free transfer.

Keeper Fraser Forster moved to Southampton in the summer for a fee believed to be close to £10million with Gary Hooper, Victor Wanyama and Kelvin Wilson having been sold for sizeable fees year.

Lawwell tried to contextualise Celtic's plight when it comes to buying players while maintaining that he will not jeopardise the club's future.

"If you look at [recent Southampton signing] Shane Long, with the greatest respect he was sold for £12m and he scored four goals last year," he said.

"We can't afford that. If you look at Ross McCormack [who joined Fulham for £11m]. We can't afford that or the wages that go along with that.

"We are well-known as being one of the best run clubs in Europe if not the world.

"Over the last 11 years we have been in the group stages of the Champions League seven times, the last-16 three times, and if we win the title this year it is eight titles in that time.

"Over that period, at the same time, the second and third largest clubs in Scotland (Rangers and Hearts) have gone bust.

"So for a club like Celtic, operating in Scotland with the financial constraints, it is a myth that we don't invest in the club and it is also a myth that we are sitting on piles of cash. That is not the case.

"We will put everything into the club that comes in, that is the commitment to the supporters

"Every penny is invested, you can't invest more than everything. But we won't put the long-term future of the club at risk."